Abstract:The research results show that dynamic background of the Ordos block is the Tibetan plateau compression from an East-West direction. The seismic activity of the Ordos block northern margin since 1970 shows that the moderate seismicity is characterized by episodic activities; moderate earthquakes of Ordos block experienced 4 curtains from 1970 to 2015, strong earthquakes of the northwestern and northeastern margins of the Ordos block has migrating characteristics, a total of 4 curtains since 1970, (before the magnitude 6 earthquake in the northern margin of the block). The moderate earthquake of the entire block has been quiet a long time according to the statistical results of earthquake examples, while moderate seismic is in a long quiet stage in Yinshan seismic zone since March 2005. The curtain activity and migrating characteristics, as well as the time calm characteristics, can be used as a prediction index for strong earthquakes in the region.
GAO Lixin,DAI Yong,CHEN Lifeng et al. Dynamic Background and Present Seismic Activity Characteristics in the Northern Margin of the Ordos Block[J]. jgg, 2017, 37(7): 668-674.